Help! Isaac Barton Easterly, b:1822 d:after 1860

I am in desperate need of a new clue!Isaac Barton Easterly, born 1822 in Marion County, TN married Sarah Stewart and moved to Jefferson County, Arkansas.He bought property and his family lived fairly prosperous lives there.For some reason, lots of people say Isaac died in TN, but I have never seen proof of that as his family was still in AR.I have read the documentation in his father's will that provides evidence that Isaac is dead by 1863, but it does not clarify when and where he died.Does anyone have actual evidence they can provide on where, how, when he died and where he is buried?Your taking time to reply would be ever so appreciated.

FYI: Sarah re-married in Dec. 1867 to William C. Castleberry (license recorded in Jefferson County, AR), a neighbor.She is buried in Camp Creek Cemetery, Grant County, AR as Sarah Stewart Easterly.

Again, thank you for your time.